Network interfaces known as Service Selection Gateways (SSGs) or Network Access Servers (NASS) terminate Layer 2 protocol connections from network users. Layer 2, or Data Link, information regards the procedures and protocols used to operate communications lines and may include information about network links such as bandwidth, latency, and utilization. The user connections may be of various types, including traditional Point-to-Point Protocol (PPP) over a dial-up connection, Point-to-Point Protocol over Ethernet (PPoE), Point-to-Point Protocol over Asynchronous Transfer Mode (ATM) (PPPoA), Point-to-Point Protocol over Ethernet over Ethernet (PPPoEoE), or other Layer 2 protocols such as GPRS Tunneling Protocol (GTP) that terminate in General Packet Radio Service (GPRS) nodes. In the traditional setting the SSGs handle user authentication and user Internet Protocol (IP) address assignment when a user logs on by using a RADIUS or other Authentication, Authorization, and Accounting (AAA) server. The SSG associates a user-ID with the IP address of that user and retains the user-ID—IP address mapping until the user logs off the network. When the user logs off the network, an “Accounting Stop” message is communicated to the AAA server, and the IP address is returned to an address pool of available addresses.
Network Service Providers (SPs) may locate some client-specific services at the edge of the network in a Point of Presence (POP) location. This enables client-specific services such as data content rating and filtering to be enabled and enforced as closely as possible to the client devices. A network interface, hereinafter referred to as a Client Services Gateway (CSG), exists “upstream” from the NAS within the POP and is operable to provide these types of client services. In order to provide client specific services in a POP, the CSG needs to associate a user-ID with a given client address in order to retrieve the user profile that specifies the services to be applied to a user request. Therefore, it is desirable to have a CSG recognize which incoming packets are associated with a given service.